Evaluate the following expression when $b = 3$ and $a = 1$. $8$ $b$ $ + 7$ $a$ $ + 7$
Answer: Substitute $3$ for ${b}$ and $1$ for ${a}$ $ = 8{(3)} + 7{(1)} + 7 $ $ = 24 + 7 + 7 $ $ = 38$